Common complications of hydrocephalus shunts: 1. infection; 2. excessive or insufficient shunting. Excessive shunt can cause epidural hematoma, low cranial pressure syndrome, cerebral cleft syndrome. Insufficient cerebrospinal fluid shunt, the patient’s visual symptoms do not improve significantly, the examination found that the ventricular enlargement still exists or the change is not obvious, the main reason is that the shunt valve pressure is inappropriate, resulting in poor cerebrospinal fluid discharge; 3, hemorrhage and intracranial pneumoperitoneum, hemorrhagic sites are mostly in the ventricles of the brain, intracerebral, or subdural, after the emergence of these problems should be closely observed, according to the situation to be dealt with; 3, ventricle lacunar syndrome, after the placement of the After placing a ventricular shunt, the ventricles become very small or slit-like. In a review of previous analyses, the incidence of ventricles presenting with cleft syndrome was 80%, 88% of patients with ventricular cleft syndrome can be completely asymptomatic, and nearly 6.5% of the 12% of patients with cleft syndrome require surgical intervention. Surgical approaches include repair of shunt obstruction at the ventricular end of the brain, replacement of the shunt valve with a higher pressure shunt to increase resistance, placement of an anti-siphon valve, or replacement of a pressure-adjustable drain; 4. Hypocranial pressure syndrome, which manifests clinically as headache, nausea, vomiting, bradycardia, or drowsiness, which are more pronounced when the patient changes position. Low cranial pressure syndrome patients in the upright position will cause excessive shunting, resulting in negative intracranial pressure; 5, isolated tetracerebral ventricular dilatation, the symptoms are mainly headache, dysphagia, low cerebral nerve palsy, ataxia, lethargy and nausea, vomiting, infants and young children have a long inspiratory respiration, bradycardia, etc., the treatment of the symptomatic patients can be taken to the tetracerebral ventricle peritoneal shunt; 6, the shunt tube system obstruction, the most common, generally accounted for 50-70%, mainly due to infection, hemorrhage, abnormally high cerebrospinal fluid protein, choroid plexus adhesion wrapping, the prevention method is to pay attention to the aseptic operation during the operation, and minimize the bleeding and infection; 7, there are other complications, such as shunt fracture, shunt fracture is mainly due to the head grows too big, shunt valve fall off and other reasons.